TURNING ORGANIC WASTE INTO FUEL AND FOOD AT WHISKEY HILL FARMS
Whiskey Hill Farms is a 14-acre organic farm on California’s Central Coast, near Watsonville.
It is is a pioneer in developing a systems approach to agricultural technology by recycling and reusing various inputs and outputs in farming and demonstrating the technology and best practices of a circular, closed-loop food economy (see figure below).
The Farm employs poly-cropping techniques of permaculture, creating food forests in its six football field-sized greenhouses. To mimic the natural world of multi-layered poly-culture, the Farm grows turmeric and gingers underground, with melons, heirloom peppers and basil varieties at ground level. They then plant vining fruits such as tomatoes, passion fruit and lemon cucumbers and finally fruit trees such as mango and papayas. The Farm’s cultivation techniques are steeped in regenerative agricultural practices making the richest, most vital soil possible to both repair damaged soil.
The Role of Soil in Regenerative Agriculture
Why Recycling Organic Wastes is Essential to Regnerative Agriculture
According to the EPA, the U.S. produces more than 100 million tons per year of food waste. In addition, there is an urgent need to address the organic waste diversion problem as soon as possible to combat climate change. If landfilled, the Nation’s organic wastes would generate 40 million tons of carbon dioxide equivalent. The Nation’s organic wastes could be converted into almost 100 million barrels of green bioethanol, compost, fertilizer and value-added products (California disposed of almost 13 million tons of compostable organic waste in landfills in 2018, which could produce 12 million barrels of ethanol). Bioethanol production could significantly reduce transportation and landfill emissions associated with waste disposal. In addition, emissions from producing and transporting corn ethanol would be reduced resulting in increased food security, soil regeneration and carbon sequestration. The waste could be transformed into valuable green products that use greenhouse gasses for useful production process thereby reducing carbon emissions. In combination with a farming operation, transformation of organic waste into climate smart products would go a long way toward making a circular economic loop in agriculture.
In California, moreover, there is an urgent need to address the disposal of organic wastes in landfills. California Senate Bill 1383 mandates a 75% reduction in landfill methane emissions from household, business, food processors and agriculture by 2023. Waste management jurisdictions are required to provide these customers with containers to collect organic wastes (mostly food) for processing and composting. However, in many instances, composting facilities are located far from points of origin and the resulting compost is not returned to the communities from which the waste came.
Blume industries and Whiskey Hill Farms together take organic wastes, turn them into ethanol, recycle many of the distillation by-products and create rich compost that is worked back into the farm’s soil. How does this happen?
Turning Organic Waste Into Ethanol
The process of turning organic farm and food processing wastes into valuable outputs begins in the biorefinery operated by Blume Distillation. Organic wastes from the farm and outside sources are cooked and turned into a liquid in a boiler fueled by methane produced by the the Farm’s biodigester (see below).
The liquids, full of sugar, starch and nutrients, are piped into fermenting tanks, to which yeast is added. In a few days, the mixture has fermented and contains about 10% ethanol alcohol. That liquid is run through a steam heating column in which the ethanol is turned into vapor and separated from the liquid for further refining and conversion into various grades of alcohol. The nutrient-rich liquids left behind in the distillation column and are piped into the farm’s methane digester (the long, plastic-covered pond), where the organic residues decompose and generate methane.
The methane is collected and returned to the biorefinery where it is burned to heat the various tanks and distillation columns.
The digestion pond is tilted and the liquid, which still contains nutrients, is pumped into the adjacent pond to feed cattails.
Many farmers regard cattails as a nuisance. They grow and spread quickly wherever there is standing water and are difficult to eradicate because their seeds spread so easily. But cattails play and essential role in closed loop, regenerative agriculture at Whisky Hill.
First, the leaves grow so quickly that the bond can be “mowed” four times a year, providing fiber and compost. Second, the heads and roots provide protein and starch, which can be turned into flour or animal feed. Third, the cattails are very efficient at removing residual nutrients from the water, whose purity exceeds California standards for agricultural runoff.
The water is put to work again, pumped into a pond full of duckweed for reoxygenation. The duckweed can also be harvested and recycled or used as animal feed.
Finally, this clean, oxygenated water can be pumped into the aquaculture pond, inhabited by catfish and “fresh water” lobsters (aka, Australian crayfish), or used for watering crops.